Turbine nozzle guide vanes for gas turbine engines generally comprise inner and outer platforms with an aerofoil extending therebetween. Such guide vanes are formed as a plurality of segments arranged in one or more rings around an engine. It is necessary for a gap to be left between adjacent guide vanes to allow for manufacturing tolerances and thermal expansion during use. These gaps are conventionally sealed by providing cooperating slots in each guide vane, with a metal seal strip extending in the slots and between the segments.
Nozzle guide vanes are generally air cooled, and passages can be provided in the platforms and aerofoil. It is generally difficult however to cool the abutment faces between adjacent vanes, and particularly due to the provision of the seal strips extending therebetween. Higher engine gas temperatures are generally now being used which make cooling of the nozzle guide vanes increasingly important.
U.S. Pat. No. 6,254,333 discloses a stator vane having platforms that abut adjacent platforms. The platforms comprise a rear attachment rail. The abutting faces of the platforms define seal slots along their lengths and are fed with cooling air from a single passageway that is located rearward of the rear attachment rail. One problem of this design is that the single rearwardly positioned hole does not provide a sufficient supply of cooling air to the slot and therefore the front part of the abutment face and platform may become overheated resulting in adverse thermal gradients that reduce the life of the vane. U.S. Pat. No. 4,902,198 discloses a similar arrangement with a similar problem.